You would need at least server.so and client.so binaries to play mods. So even if they release the SDK, mods' devs will have to port / recompile their mods for Linux.

I know, I know but BM guys wrote

Will Black Mesa be ported to Xbox360, Mac or another platform?

At the moment Black Mesa supports only PCs powered by Microsoft Windows operating system. No support for Mac or port for Xbox360 (although the Xbox360 controller is supported). Linux will be supported only if developers could port the codebase over easily.

Agree. This whole Steam for Linux ordeal has been a great change of pace for Linux gaming and whatnot, but we're missing out on one of the things Linux has always been great for: coding! I'm sure this won't happen for a while, since the Source engine is still rapidly changing under Linux, and I doubt all of the SDK tools will be easily ported to Linux. Here's to hoping it's soon.